mattchew

HI Guys about to service the scooby and need to know if i need colder plugs and iff so what grade

going to be going for the ngk irriduim spark plugs but do i need grade 6 7 or 8

mods are

simtek ecu remapped to 350 bhp
running 1.5 bar boost
full 3 inch decatted turbo back
afterburner peformance filter
snorkus delete mod

would colder plugs be a good idea if not what grade is standard lol?

cheers

Tim W

iTrader: (1)

Standard Grade for a UK car is PFR6B
Standard for an Sti is PFR7B

PFR7B's should be fine at your power level

mattchew

so is that grade 7 then?

cheers

PeeVee

iTrader: (1)

Yes mate you need a grade 7.

GazTheHat

NGK PFR7B from: Roger Clark Motorsport - Home

JohnD

iTrader: (5)

NO - STi's use PFR6G as standard. Going to a 7B (or G) is only necessary if you are above the 320 mark as is reducing the plug gap from 0.8mm standard, to 0.65 - 0.70mm (to reduce possibility of spark blow-out due to raised boost level) So, as stated, yours will be fine with 7B's or the iridium equivalent and if you'll be running 1.5bar, take the gap down to 0.65mm.

JohnD